The invention relates to a clamp for connecting form panels which are disposed in coplanar, side-by-side relation and have edge webs or edge sections along at least two confronting edges, and preferably along all of the edges, whereby the clamp has two clamping jaws adapted to be urged against the oppositely directed longitudinal faces of the adjacent edge webs or edge sections, a carrier connecting the clamping jaws and an actuating element for swivelling the first clamping jaw, whereby the second clamping jaw is connected to the carrier at a fixed or invariable angle, preferably in a permanent fashion, and the first clamping jaw is slidable relative to, and in the longitudinal direction of, the carrier and in different positions of travel is adapted to swivel about an axis oriented transversely to the carrier by means of a wedge, eccentric or similar adjusting element.
A clamp of this general type is known, by way of example, from EP-0 537403 A. In that reference, the swivelling first clamping jaw has a bolt that traverses the carrier to form the swivel axis. Extending lengthwise of the carrier, at its back remote from the clamping jaws, is a slot which serves for guidance of a wedge element arranged there. In addition, further slots are provided in the side faces of the carrier which are arranged at right angles to the back. Such slots have a toothing on the side which comes under pressure from the joint of the first clamping jaw when the clamp is tightened and the bolt serving as the swivel axis can be selectively inserted in the tooth spaces. Therefore the first clamping jaw can be adjusted into different positions only stepwise according to the tooth spacing. The user hence has to predetermine precisely in which of the possible positions the clamping jaw will exert its optimal clamping force. Since for the purposes of horizontal adjustment, it may perhaps be necessary for intermediate pieces of different sizes to be placed between two edge sections of adjacent form panels, the outsides of the edge sections may come to be at a spacing for which none of the fixed tooth positions of the swivelling clamping jaw is best for an optimal transfer of clamping force.
The wedge arranged at the back of the carrier for swivelling the first clamping jaw engages behind a transverse bolt which connects the two parallel portions of this clamping jaw and is arranged in spaced relationship to the swivel axis of the clamping jaw, so that a corresponding lever arm is produced.
Apart from the fact that with this known clamp the first clamping jaw can be adjusted only stepwise, high friction forces and cramming forces are induced during its swivel movement by the wedge inserted between the back and this bolt belonging to the clamping jaw. Therefore the user cannot be sure that, given a tight fit of the wedge, the maximum clamping force really is generated. Furthermore, a special wedge is necessary which requires appropriate guide means for engagement with the longitudinal guide at the back of the carrier. It hence follows that, all in all, production is complicated, also as a result of the toothing.
During the swivel movement, due to the force component oriented approximately at right angles to the carrier, the swivel bearing is subjected to ever increasing pressure in this arrangement, so that the frictional forces in this bearing increase. At least part of the forces applied by the wedge is hence used within the bearing and is not available as clamping force.